The invention relates to an improved process for converting non-aromatic hydrocarbons in the presence of an improved zeolite material to aromatic and lower olefin hydrocarbons during the conversion of such hydrocarbons in the presence of such improved zeolite material.
It is known to catalytically crack non-aromatic gasoline boiling range hydrocarbons (in particular paraffins and olefins) to lower olefins (such as ethylene and propylene) and aromatic hydrocarbons (such as benzene, toluene, and xylenes) in the presence of catalysts which contain a zeolite (such as ZSM-5), as is described in an article by N. Y. Chen et al in Industrial & Engineering Chemistry Process Design and Development, Volume 25, 1986, pages 151-155. The reaction product of this catalytic cracking process contains a multitude of hydrocarbons such as unconverted C.sub.5 +alkanes, lower alkanes (methane, ethane, propane), lower alkenes (ethylene and propylene), C.sub.6 -C.sub.8 aromatic hydrocarbons (benzene, toluene, xylenes, and ethylbenzene), and C.sub.9 +aromatic hydrocarbons. Depending upon the relative market prices of the individual reaction products, it can be desirable to increase the yield of certain of the more valuable products relative to the others.